The long-term objective of this research is to develop a detailed, atomic-resolution structural and functional understanding of protein aggregation and fibrillation relevant to human disease, principally with studies of alpha-synuclein. Wild type alpha-synuclein and its mutants (A30P, E46K and A53T) associated with early- onset Parkinson's disease (PD) will be examined in several structural states, including protofibrils, fibrils and membrane-associated complexes. We propose that the chemical details of these structures determine the natural physiological function of alpha-synuclein and, in the mutants and/or under environmental stress, contribute to PD pathology. Moreover, we propose that conversion among several structural states is an essential feature of synucleins;this structural plasticity is likely to be required for neuronal development and maintenance. To examine these structures, magic-angle spinning (MAS) solid-state NMR (SSNMR) experiments will be employed, elucidating details of conformation and dynamics that are inaccessible to other experimental techniques. PUBLIC HEALTH RELEVANCE: Alpha-synuclein is a central player in Parkinson's disease. The precise relationships between alpha-synuclein structure and this disease are not yet well understood. Our proposed studies aim to advance this fundamental knowledge, which will assist the broader research community in developing improved diagnostic tools and therapies for Parkinson's disease.